Electric switch assembly including indicator and mounting means



Nov. 10, 1964 H. E. BAKER ETAL 5 ELECTRIC SWITCH ASSEMBLY INCLUDINGINDICATOR ANDMOUNTING MEANS Filed July 22, 1960 2 Sheets-Sheet 1 HAROLDE. BAKER ERLE H.DODGE MARCELLUS N. GILBERT JR fig. Z I INVENTORS BY 6 M,

ATTORNE Nov. 10, 1964 H. E. BAKER ETAL 3,156,805

ELECTRIC SWITCH ASSEMBLY INCLUDING INDICATOR AND MOUNTING MEANS FiledJuly 22, 1960 2 Sheets-Sheet 2 HAROLD E. BAKER ERLE H. DODGE MARCELLUSN. GILBERT JR.

INVENTORS BY C M! ATTOR Y United States Patent 3,156,805 ELECTRIC SWITCHASSEMBLY INCLUDING INDI- CATOR AND MOUNTING MEANS Harold E. Baker,Danvers, Erle H. Dodge, Beverly, and Marcellus N. Gilbert, Ira,Lynntield, Mass, assignors to Sylvania Electric Products Inc, acorporation of Delaware Filed July 22, 1960, Ser. No. 44,591 7 Claims.(Cl. 200-167) This invention relates to electric switches and moreparticularly to modifications of conventional electric switches andmounting arrangements employed in locating them in operational positionsin various applications.

The type of electric switch with which this invention is particularlyconcerned is the mechanically actuated type in which an actuating arm ismechanically connected to a switch contact. In this type of switch,displacement of the actuating arm effects a displacement of the switchcontact associated therewith to either close or open an electricalcircuit through this switch contact and at least one other switchcontact associated therewith. Switches of this type are usually providedwith threaded receptacles in the bottom thereof for receiving screws. Insome cases wires are connected directly to these screws and in othercases metal tabs are supported at one end by these screws and the wiresare soldered, welded or crimped to the other ends of these tabs, inorder to connect the switch electrically in a circuit. These switchesare provided withsome form of mounting means, usually a pair of holesextending transversely therethrough, so that the switch may be'locatedand positioned on some mounting surface, such as a pair of plugs forexample.

In the practical usage of these switches, as those skilled in the artknow well, it is quite important that great care be exercised inaccurately locating the mounting plugs for these switches because theproper operation of the switch depends thereon. If the switch is notproperly located, insofar as its mounting is concerned, its actuatingarm will not be properly located and malfunctions will occur. Expediencymany times suggests that the actuating arm be permanently bent in adirection and to the extent necessary to compensate for thisinaccurateswi-tch mounting. Many times the switch mechanism is damagedwhen this is done. And in all cases, the problem has not been solved butmerely avoided and must be faced again when a new switch is installed atthe same location.

Another problem, with which those skilled in the art are familiar, isthe difliculty in determining whether or not the switch itself isoperating properly when some failure occurs in the electrical circuitrywith which the switch is associated. This problem is further aggravatedwhen a whole bank of these switches is used in one general operation.The further question then arises as to which switch is the defectiveone.

In view of the foregoing circumstances, an object of this invention isto provide a mounting arrangement for electric switches which readilylends itself to adjustment both upon initial installation and duringusage.

Another object is to providesuch a mounting arrange ment which furtherlends itself to a quick and easy replacement of a defective switch by agood one with the assurance that the mounting arrangement will not bedisturbed and the new switch will operate properly.

A further object is to providean electric switch assembly with visualindicating means from which it can be readily determined whether or nota detected malfunction is-due' to a faulty switch.

A further object is to provide an electric switch assembly with meansfor protecting the switch actuating arm aliases from damage and moreparticularly for preventing abnormal overtravel thereof and thus protectthe switch from damage which could well be permanent and necessitatereplacement of the switch by a new one.

These and other objects, advantages and features are attained, inaccordance with the principles of our invention, by mounting a switch onan adjustable mounting plate which can be adjusted in one or moredirections and by incorporating in a switch receptacle a visualindicating means electrically connected to the switch. In the switchassembly of our invention, the locus of the switch itself thereon isalways the same but the locus of the mounting plate can be adjusteddepending on the circumstances. Once the locus of the mounting plate hasbeen determined accurately it is secured in position so that when aswitch replacement is made it is known that the switch willautomatically be in the correct position. An actuating lever, pivotallymounted on the aforementioned mounting plate, normally engages theswitch actuating arm and limits its travel so that malfunctions due toovertravel of the actuating arm are avoided.

In the accompanying drawings illustrating a specific embodiment of ourinvention,

FIGURE 1 is an exploded View of a switch assembly.

FIGURE 2 is a side elevational view of the switch assembly of FIGURE 1showing the parts thereof in the assembled state.

FIGURE 3 is a side elevational view of the switch assembly of FIGURE 2disposed on one type of mounting plate. 7

FIGURE 4 is a side elevational view of a modified switch assemblydisposed on another type of mounting plate.

FIGURE 5 is a vertical section through the visual indicating meanscomponent of the switch assembly taken along the line 5-5 of FIGURE 6.

FIGURE 6 is a transverse section through the visual indicating meanscomponent of the switch assembly taken along the line 66 of FIGURE 5.

Referring now to FIGURE 1, the electric switch It) illustrated thereincomprises a body member 12 within which the switch contacts aredisposed, a switch actuating arm 14- pivotally mounted at 16 on the bodymember 12 and a pair of resilient plugs 18 depending from the bottom ofthe body member 12. A pair of switch mounting holes 20 extendtransversely through the body member 12. The switch Ill is the same as acommercially available switch except that the pair of resilient plugs 18replace the pair of terminal screws and terminal tabs normally a part ofswitches of this type.

Disposed immediately beneath and in cooperative relationship with theswitch it) is a translucent case 22 within which a visual indicatingmeans described more fully below is disposed. The translucent case 22comprises a base member 24 and a body member 26. A pair of mountingholes 28 extend transversely through the body member 25. A pair of holes3% extend vertically through the case 22. A pair of hollow screws 32provided with washers 34 extend into the holes 3% in the case 22 anddefine receptacles for receiving the resilient plugs 18 depending fromthe switch til and for establishing electrical connections therewith.

The assembled switch 10 and case 22 are seated in a receptacle 35 with asleeve 38 of insulating material disposed therebetween. The sleeve 38 isprovided with holes 4%, the purpose of which will be described below.

The receptacle 36 is provided with a pair of holes 42' in the bodymember 2-6 of case 22 when these components are assembled. As will benoted in FIGURE 2, screws 46 extend through this last mentioned seriesof holes to secure the case 22; in the receptacle 35. The receptacle 36is provided with a translucent base plate 48 secured thereto by screws50. The receptacle 36 is also provided with an internally threaded boss52 for receivng an electrical connector to be described below.

As mentioned above, the translucent case 22 is provided with a visualindicating means. This is shown particularly in FIGURES and 6, to whichparticular reference is now made. The visual indicating means comprisesan indicator lamp 5d and a resistor 56 connected in series across thehollow terminal screws 32 by terminal tabs 58a, 53b and 580. This visualindicating means assembly is mounted on the base member 24 of the case22 and is enclosed by the body member 26 thereof. The terminal tab 58::is common whereas terminal tab 581'; or terminal tab 580 will be the tabengaged by one of the terminal screws 32 depending on whether thecorresponding plug 18 (FIGURE 1) of the switch 19 is disposed in thenormally closed circuit receptacle or normally open circuit receptaclein the bottom of the switch Ittl.

One type of switch assembly mounting structure is illustrated in FIGURE3. In the modification shown therein, the switch assembly of FIGURE 2 issecured to an adjustable switch mounting plate 65 which is in turnsecured to an adjustable base plate 62. The switch mounting plate 65' isprovided with a pair of switch mounting pins 64 and a resilient clipMounting of the switch assembly on the switch mounting plate 69 iseffected by positioning the switch assembly thereon with the mountingpins 64 projecting through the holes 29 provided therefor in the bodymember 12 of the switch and snapping the resilient clip 66 over theouter face of the receptacle as. An electrical connection to the switchassembly is made by a cable 68 having wires 79 running therethrough anda threaded plug 72 on the end thereof, the plug 72 being screwed intothe threaded boss 52 and the wires 7i being connected to the terminalscrews 32 (FTGURE 1) within the receptacle 36. The switch mounting plate60 is provided with a pair of openings therein, such as elongated holes74 for example. Positioning of the switch mounting plate 6t) on the baseplate 62 is adjustable within the limits defined by the elongated holes74 in the plate tit). Once the desired lateral positioning of switchmounting plate 60 has been determined, the plate on is secured to thebase plate 62 by screws 76. Vertical adjustment of this assembly canthen be eifected by adjusting the position of the base plate 62, whichis attached to a suitable member, not shown, of the apparatus with whichthe switch is to be associated. Positioning of the base plate 62 isadjustable within the limits defined by openings therein, such as theelongated holes 78 for example. Once the desired vertical positioning ofthe base plate 62 has been determined, it is secured in position byscrews 89.

As was mentioned above, one of the objects of this invention is toprovide an electric switch assembly with means for protecting the switchactuating arm from damage, including prevention or" abnormal overtravelthereof and thus protect the switch mechanism from damage which couldwell be permanent and necessitate replacement of the switch by a newone. This means is illustrated in FIGURE 3. As shown in this figure, alever 82 is pivotally mounted at 84 on base plate 62. The lever 82overlies the switch actuator arm Li and a portion of the lowerlongitudinal edge thereof normally engages the actuator arm. The lever82 is spring-loaded clockwise by spring 86 and is provided with a hole83 intermediate its ends and through which pin 9t) on base plate 62extends. A suitable contact arm or member, such as for example contactarm 92., is attached to lever 82 by screws )4.

The assembly just described is shown in its normal rest position inFIGURE 3. In operation, the free end of the contact arm 92 is displaceddownwardly as indicated by the arrow shown immediately therebeneath.Downward movement of the contact arm 92 effects a similar movement ofthe lever 32 to which it is attached, the lever 82 movingcounter-clockwise and pivoting about its pivot point 84. Since the lever82 normally engages the switch actuator arm 14 which is pivoted at 16,the switch actuator arm 14 is similarly displaced and thus actuates theswitch. The length of the stroke of the lever 82 is limited by the pin9:), further downward travel of the lever 82 being arrested as soon asthe lever strikes the upper periph ral surface of the pin 99 projectingthrough the hole 38 in the lever. Thus this pin-hole arrangementprevents an overtravel stroke being applied to the switch actuator arm14- during the switch actuating stroke thereof. Once the force appliedto the free end of contact arm 92 to actuate the switch has beenrelieved, the spring 86 returns the lever 82 to its normal rest positionand thus permits the switch actuator arm 14, which is also a springloaded member, to return to its normal rest position. One end of spring86 fits in hole 87 provided therefor in lever 82 whereas the other endthereof fits in one of several holes 39 provided therefor in switchmounting plate 69, the selection of the particular hole %9 depending onthe amount of tension which it is desired to have the spring exert onthe lever.

Another modification of the switch assembly of our invention isillustrated in FIGURE 4. The modification shown in FIGURE 4 isparticularly suitable for applications where damage to the switch suchas for example possible overtravel of the switch actuator arm is not asubstantial problem and only adjustability of the switch assembly isrequired. In this embodiment, the switch assembly of FIGURE 2 ispositioned on switch mounting plate 9a with mounting pins 98 thereonprojecting through roles provided therefor in the body member of theswitch, and resilient clip 10% mounted on the plate 96 snapping over thereceptacle 101 to hold it on the plate. Actuator arm 14a of the switch,pivotally mounted at 16a, is provided with a roller 102 on the free endthereof. Thus when the roller 102 is engaged, such as by an article ofwork passing thereover for example, the actuator arm 14a is deflecteddownwardly and thus effects energization of the switch. Electricalconnections to the switch assembly are made in the same manner asdescribed above in connection with FIGURE 3. The mounting plate 96 isadjustable within the limits defined by the elongated slots 1% therein(one of which is shown). When this adjustment has been determined, theplate 96 is secured in posi tion by screws 108 (one of which is shown).

As noted above, the switch assembly of our invention includes a visualindicating means disposed within a translucent case. The specificembodiment of this visual indicating means comprises an indicator lamp54 across the terminal screws 32. Thus each time the switch is actuated,the lamp glows and provides a readily visible signal that the switch isoperating. If the switch becomes defective the lamp will not go oh? andon but stay off or stay on depending on just when in an operating cyclethe defect developed. An inspector or operator in attendance willreadily note the unchanged state of this visual signal and thus bealerted to the realization that the switch is defective and must bereplaced.

Replacement of a defective switch may be effected quite readily by anoperator since the switch 10 merely plugs into the hollow terminalscrews 32 projecting up through the translucent case 2.2. Since no partof the assembly associated with the switch has to be disturbed duringthis replacement operation, the new switch, when plugged in as noted,will necessarily be accurately located for proper operation.

One of the more important practical advantages of the switch assembly ofour invention is its ready adaptability to a variety of applicationcircumstances. For example, the switch body member 12 may be positioned1n the receptacle 36 so that its switch actuator arm 14 extends to theleft or to the right. The resilient clip 66 of FIGURE 3 and theresilient clip 100 of FIGURE 4 may be relocated on their respectivemounting plates to the right instead of to the left as shown in order topermit reversal of the location of the electrical connections. Also, theposition of lever 82 of FIGURE 3 may be similarly reversed so that itextends to the right instead of to the left.

What we claim is:

1. An electric switch assembly comprising: a switch body member; a pairof terminal plugs depending from the bottom of said body member; atranslucent case disposed in abutting relationship with respect to thebottom of said body member, said case having a pair of holes extendingtherethrough and in register with said terminal plugs; a pair of hollowterminal screws extending into said holes from the bottom of said case,said plugs extending into and engaging said screws; and a light sourcedisposed in said case and electrically connected across said screws.

2. The combination of claim 1 and a receptacle within which said switchbody member and said case is disposed, portions of said receptacle beingcutaway to expose substantial portions of said case disposed thereinwhereby said light source is visible.

3. The combination of claim 1 and a receptacle within which said switchbody member and said case is disposed, the bottom of said receptaclehaving a translucent plate whereby said light source is visible from thebottom thereof, and the sides of said receptacle being cutaway to exposesubstantial portions of said case disposed therein whereby said lightsource is visible from the sides thereof.

4. The combination of claim 1 and a receptacle within which said switchbody member and said case is disposed, the bottom of said receptaclehaving a translucent plate whereby said light source is visible from thebottom thereof, the sides of said receptacle being cut away to exposesubstantial portions of said case disposed therein whereby said lightsource is visible from the sides thereof, and an end of said receptaclebeing provided with an opening through which wires may be fed forconnection to said terminal screws.

5. In combination with an electric switch having a body member and anactuating arm pivotally mounted on the top thereof for repetitiveengagement by objects moving through a path: a pair of terminal plugsdepending from the bottom of said body member; a translucent casedisposed in abutting relationship with respect to the bottom of saidbody member, said case having a pair of holes extending therethrough andin register with said terminal plugs; a pair of hollow terminal screwsextending into said holes from the bottom of said case, said plugsextending into and engaging said screws; a light source disposed in saidcase and electrically connected across said screws; a mounting plate;and means for securing said switch to said mounting plate, said mountingplate having a pair of elongated slots cut therein whereby and throughwhich said mounting plate can be adjustably positioned and attached to abase member, said adjustable positioning of said mounting plateproviding means for accurately locating said switch actuating arm insaid path.

6. In combination with an electric switch having a switch actuating armpivotally mounted thereon for repetitive engagement by objects movingthrough a path: a mounting plate on which said switch is mounted, saidplate having a pair of elongated slots cut therein and extending in onedirection; means on said mounting plate through which said switch isattached thereto; a base plate for said switch mounting plate, said baseplate having a pair of elongated slots cut therein and extending in adirection transverse to the direction in which said first-mentioned pairof slots extend; means extending through said first-mentioned pair ofslots for securing said mounting plate to said base plate; and meansextending through said second-mentioned pair of slots for securing saidbase plate, said first-mentioned pair of slots and said second-mentionedpair of slots providing means for adjustably positioning said switch intwo different planes for accurately locating said switch actuating armin said path.

7. In combination with an electric switch having a switch actuating armpivotally mounted thereon: a mounting plate on which said switch ismounted; means on said mounting plate through which said switch isattached thereto; a lever pivotally mounted on said mounting plate andin register with said switch actuating arm with -a portion of the lowerlongitudinal side of said lever in engagement with said switch actuatingarm near the free end thereof for actuation thereof; and means fordefining the limits of displacement of said lever whereby the limits ofdisplacement of said arm actuated by said lever are controlled thereby.

References Cited in the file of this patent UNITED STATES PATENTS1,152,005 Clark Aug. 31, 1915 1,503,238 Gall July 29, 1924 2,377,912 WayJune 12, 1945 2,454,341 Repka Nov. 23, 1948 2,633,520 Chandler et alMar. 31, 1953. 2,748,219 Buchanan May 29, 1956 2,767,276 Buchanan et alOct. 16, 1956 2,785,256 Nina Mar. 12, 1957 2,789,176 Mercier Apr. 16,1957 2,866,964 Neidenberg et al Dec. 30, 1958 3,027,441 Mullen et a1Mar. 27, 1962

1. AN ELECTRIC SWITCH ASSEMBLY COMPRISING: A SWITCH BODY MEMBER; A PAIROF TERMINAL PLUGS DEPENDING FROM THE BOTTOM OF SAID BODY MEMBER; ATRANSLUCENT CASE DISPOSED IN ABUTTING RELATIONSHIP WITH RESPECT TO THEBOTTOM OF SAID BODY MEMBER, SAID CASE HAVING A PAIR OF HOLES EXTENDINGTHERETHROUGH AND IN REGISTER WITH SAID TERMINAL